Corresponding author: Vunder Nina A., Postgraduate Student of the Department of Control Systems and Informatics, ITMO University, St. Petersburg, 197101, Russian Federation,
e-mail: polinova_nina@mail.ru

Received on December 09, 2016
Accepted on June 01, 2017
The article proposes an analytical design algorithm of a consecutive compensator in the control system of a plant with amplitude modulation. The modulation is generated by using an induction motor as an actuator. This type of systems is called "quasi-discrete" because an information transmission using a harmonic carrier signal is carried out by its half-waves, that means discretely such that a discrete interval is equal to the half-period of the carrier signal. The algorithm is based on typical polynomial models parameterized by characteristic frequency. Analytical representations of quality indicators of systems with typical polynomial model are presented in the article. The bandwidth is associated with the characteristic frequency at the level of small values of the amplitude frequency response of the system. At the same time, system quality indicators are associated with frequency of the carrier signal, this follows from the Kotel'nikov-Shannon's theorem. This became the basis of the proposed algorithm. Thus, the complete algorithm of the design of control systems with target quality indicators for plants with amplitude modulation is received in this work. Results are illustrated by an example of design of a servomotor drive with an AC motor. The main power frequencies of induction motors are 50 Hz and 400 (500) Hz. Therefore, the results are oriented to these values of the signal carrier frequencies.
Keywords: typical polynomial model, characteristic frequency, amplitude modulation, stability, Kotel'nikov-Shannon's theorem, frequency of the carrier signal, quality indicators, analytical design algorithm of consecutive compensator

Acknowledgements: This work was supported by the Government of the Russian Federation, Grant 074-U01; Ministry of Education and Science of the Russian Federation, Project 14.Z50.31.0031; Russian Federation President Grant № 14.Y31.16.9281-НШ.